1. Field of the Invention
The present invention relates to a three-dimensional semiconductor device and a method of manufacturing the same.
2. Description of the Related Art
A conventional semiconductor device having a heat transfer structure is disclosed in Japanese Patent Application Laid-open No. Hei. 9-246466, as shown in FIG. 10. FIG. 10 is a schematic cross-sectional view of the conventional semiconductor device in a thickness direction of an IC package 112. The conventional semiconductor device shown in FIG. 10 will be described as follows.
The IC package 112 is provided with an IC chip 107 in a cavity 118. The IC chip 107 is electrically and mechanically connected to the IC package 112, and sealed off by a cap 117 in a hollow state. A radiating fin 119 is attached on to a surface of the IC package 112 opposite to a surface on which the IC chip 107 is mounted. The radiating fin 119 is placed on the IC package 112 in a position identical to that of the IC chip 107 in a thickness direction, in such a manner that the radiating fin 119 overlaps the IC chip 107 via the IC package 112 in a thickness direction of the IC chip 107.
Furthermore, on the reverse surface of the IC package 112 (i.e., the surface of the IC package 112 to which the radiating fin 119 is attached), a land 114 is formed for electrically and mechanically connecting the IC package 112 to an IC package 115 having substantially the same structure as that of the IC package 112 with long pins 116. On the under surface of the IC package 112, pins 113 are formed for electrical and mechanical connection to a mounting substrate 101. Thus, the first-stage IC package 112 close to the mounting substrate 101 is constructed.
Next, the second-stage IC package 115 is provided with an IC chip 107 in a cavity 118. The IC chip 107 is electrically and mechanically connected to the IC package 115. In the IC package 115, the IC chip 107 is sealed off in the cavity 118 in a hollow state, in the same way as in the IC package 112.
A radiating fin 120 is attached onto a surface of the IC package 115 opposite to a surface on which the IC chip 107 is mounted. The radiating fin 120 is placed on the IC package 115 in a position identical to that of the IC chip 107 in a thickness direction, in such a manner that the radiating fin 120 overlaps the IC chip 107 via the IC package 115 in a thickness direction of the IC chip 107. Furthermore, on the under surface of the IC package 115, long pins 116 are formed for electrically and mechanically connecting the IC package 115 to the IC package 112. The conventional semiconductor device having a heat transfer structure. is constructed in such a manner that the IC packages 112 and 115 are mounted on the mounting substrate 101 so as to be stacked on top of the other.
Because of the above-mentioned structure, the conventional semiconductor device having a heat transfer structure allows air to flow freely through a space between the respective IC packages and does to be attached a heat sink such as a radiating fin, so that a heat transfer property can be substantially improved.
In the above-mentioned prior art, IC packages provided with semiconductor devices in cavities are stacked on top of another via pins and long pins. A large space is kept between the first-stage IC package and the second-stage IC package by using long pins so as to attach a radiating fin to the first-stage IC package, and the second-stage IC package is also provided with a radiating fin.
Consequently, the above-mentioned prior art has the following problems. An IC package has a size much larger than that of the semiconductor device, resulting in a decrease in a packaging density. Furthermore, a wiring length between the semiconductor devices is long, which makes it impossible to realize a high-speed operation. Furthermore, in a multi-stage three-dimensional semiconductor device, a wiring length is large, so that electrical characteristics are degraded. Furthermore, since the entire semiconductor device becomes very long, mechanical characteristics are also degraded. A heat transfer region is only limited to an IC package and a radiating fin, so that heat transfer to a mother board and a housing cannot be expected, which leads to a decrease in a heat transfer effect. Since a semiconductor device cannot be mounted on a curved surface, its mounting place is limited to a flat surface.
An object of the present invention is to provide a three-dimensional semiconductor device with which at least one of the above-mentioned problems maybe solved. Also, the present invention. has an object to provide a method of manufacturing the three-dimensional semiconductor device. Further, the present invention has an object to provide an apparatus for manufacturing the three-dimensional semiconductor device.
The three-dimensional semiconductor device according to a first aspect of the present invention includes: a supporting member having a three-dimensional shape allowing a plurality of semiconductor devices to be arranged in a columnar shape and containing as a main component a high heat-conductive material; and a plurality of semiconductor devices attached to the supporting member.
The method of manufacturing a three-dimensional semiconductor device according to a second aspect of the present invention includes the step of combining members having semiconductor devices attached thereto and containing as the main component a high heat-conductive material, thereby obtaining a three-dimensional semiconductor device including a supporting member that has a three-dimensional shape allowing a plurality of semiconductor devices to be arranged in a columnar shape and contains as the main component a high heat-conductive material, and a plurality of semiconductor devices attached to the supporting member.
The method of manufacturing a three-dimensional semiconductor device according to the third aspect of the present invention includes the step of attaching a plurality of semiconductor devices to a supporting member that has a three-dimensional shape allowing a plurality of semiconductor devices to be arranged in a columnar shape and that contains as the main component a high heat-conductive material.
The apparatus for manufacturing a three-dimensional semiconductor device according to a fourth aspect of the present invention includes: a stage having a surface for allowing a cylindrical structure containing as the main component a high heat-conductive material to come into contact with; a bonding head for bonding a semiconductor device to an inner peripheral surface or an outer peripheral surface of the cylindrical structure by flip-chip bonding; and rotation means for rotating the cylindrical structure on a central axis thereof and pressing the cylindrical structure perpendicularly to the stage surface.
Thus, the invention described herein makes possible the advantages of (1) providing a three-dimensional semiconductor device that overcomes at least one of the above-mentioned problems, (2) providing a method of manufacturing the three-dimensional semiconductor device, and (3) providing an apparatus for manufacturing the three-dimensional semiconductor device.
These and other advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed description with reference to the accompanying figures.